- "Tubes form when fluid lava flows down the sides of volcanoes, the upper layer begins to cool, and the lava beneath continues to flow in tubular conduits beneath the surface. Due to the insulating effects of the hardened lava above, molten lava is able to travel a considerable distance underground with very little cooling. In Hawaii, lava tubes have carried fluid lavas 50 or more miles from their source." Source - The Virtual Cave.
In our case we were able to explore about half a mile of tube.
Descending into the dark;
It's completely dark in the tube so how does this bracken plant grow here?
And another question I have for you geologists out there. In one small section (about 20m long) of the tube the floor was covered in these round boulders, which I would normally expect in a river or glacial valley, all other parts of the tube floor were rough lava or cinder. So why are they there and where did they come form? And why did they all stop in one place?
In another part of the tube the ceiling was covered in 'Hershey Kisses' chocolate stalactites;
Close-up on the chocolate stalactites;
Is there any niece, nephew or godchild who can tell us how these are formed?
At one point of the tunnel a boulder had blocked the lava flow for a while which created a blow hole through the roof of the tunnel until the lava could find another route round.
Jakki under the blow hole.
Another amazing Hawaiian experience.
No comments:
Post a Comment